Sage Journals: Discover world-class research

Abstract

Hydrous cerium–zirconium oxide (Ce_0.25Zr_0.75O₂) was used for Cr(VI) removal by adsorption. The response surface methodology (RSM) was applied as a tool for the optimization of adsorption operational conditions (temperature, pH and adsorbent dose) with the combined effects of the key processing variables on the Cr removal efficiency (%R_Cr). The following conditions were found to be optimal: pH = 2, temperature = 28 °C, adsorbent dose = 4 g l⁻¹. The %R_Cr obtained experimentally (92%) was in agreement with the value predicted by RSM (88%). The adsorption process followed the pseudo-second-order kinetic model and obeyed the Langmuir isotherm model. Thermodynamic parameters (ΔH°, ΔS° and ΔG°) indicated the exothermic and spontaneous nature of adsorption governed by physisorption interactions. Hydrous Ce_0.25Zr_0.75O₂ showed high adsorption capacity (25 mg g⁻¹), high desorption efficiency (80%), reached adsorption equilibrium quickly (30 minutes) and high chemical stability. The Cr(VI) adsorption on hydrous Ce_0.25Zr_0.75O₂ was not completely reversible. The reduction of Cr(VI) to Cr(III) under acidic conditions was also responsible for Cr(VI) removal.

References

Rodrigues

Alvares L.

Maschio

L.J.

de Silva

Evangelista R.

and de Silva

Caetano Pinto M.L.

(2010) J. Hazard. Mater. 173, 630.

Alvarez-Ayuso

Garcia-Sanchez

and Querol

, (2007) J. Hazard. Mater. 142, 191.

American Public Health Association (2005) Standard Methods for the Examination of Water and Wastewater, 21st Ed., Washington, DC, p. 367.

Anirudhan

T.S.

Jalajamony

and Suchithra

P.S.

(2009) Colloids Surf. A. 335, 107.

Campbell

C.T.

and Peden

C.H.F.

(2005) Science. 309, 752.

Dana

and Sayari

(2011) Chem. Eng. J. 167, 91.

Debnath

and Ghosh

U.C.

(2008) J. Chem. Thermodyn. 40, 67.

Di Paola

Ikeda

Marcì

Ohtani

and Palmisano

(2001) Inter. J. Photoenergy. 3, 171.

Ghosh

U.C.

Desgupta

Debnath

and Bhat

S.C.

(2003) Water Air Soil Pollut. 143, 245.

10.

GilPavas

Dobrosz-Gómez

and Gómez-García

M.Á.

(2012) Water Sci. Technol. 65, 1795.

11.

Goswami

Bhat

S.C.

and Ghosh

U.C.

(2006) Water. Environ. Res. 78, 986.

12.

Goswami

and Ghosh

U.C.

(2005) Water SA. 31, 597.

13.

Han

Deng

Huang

and Luo

(2013) J. Hazard. Mater. 254–255, 301.

14.

Chen

G.H.

and Lo

I.M.C.

(2006) J. Environ. Eng. 132, 709.

15.

Chen

Zhu

and Wang

(2009) J. Hazard. Mater. 162, 1542.

16.

Hua

Zhang

Pan

Zhang

and Zhang

(2012) J. Hazard. Mater. 211–212, 317 (and references therein).

17.

IDEAM home page (2013). https://documentacion.ideam.gov.co/openbiblio/Bvirtual/publicaciones/publicaciones2.html (Last accessed date: June 12, 2013).

18.

Jain

Garga

V.K.

and Kadirvelu

(2009) J. Hazard. Mater. 162, 365.

19.

Kalavathy

H.M.

Regupathi

Pillai

M.G.

and Miranda

L.R.

(2009) Colloids Surf. B 70, 35.

20.

Khalfaoui

Knani

Hachicha

and Lamine

(2003) J. Colloid Interface Sci. 263, 350.

21.

Liu

Sun

Yin

and Hu

, (2008) J. Hazard. Mater. 151, 616.

22.

Liu

S.X.

Chen

X.Y.

Liu

Z.F.

and Wang

H.L.

(2007) J. Hazard. Mater. 141, 315.

23.

Montgomery

(2005) Design and Analysis of Experiments, 5th Ed., Wiley and Sons, Hoboken, NJ.

24.

Mor

Ravindra

and Bishnoi

N.R.

(2007) Bioresour. Technol. 98, 954.

25.

Mukhopadhyaya

Sundq

and Schmitzc

R.J.

(2007) J. Environ. Manage. 82, 66.

26.

Namasivayam

and Sangeetha

(2004) J. Colloid Interface Sci. 280, 359.

27.

Patterson

J.W.

(1985) Industrial Wastewater Treatment Technology, 2nd Ed., Butterworth-Heinemann, London, UK.

28.

Recillas

Colón

Casals

Gonzáles

Puntes

Sánchez

and Font

(2010) J. Hazard. Mater. 184, 425.

29.

Sarin

and Pant

K.K.

(2006) Bioresour. Technol. 97, 15.

30.

Shriver

D.F.

Atkins

P.W.

and Langford

C.H.

(1994) Inorganic Chemistry, 2nd Ed., Oxford University Press, Oxford, UK.

31.

Tel

Altas

and Taner

M.S.

(2004) J. Hazard. Mater. B 112, 225.

32.

Ceballos

Vargas A.D.

García

Gómez M.Á.

and Dobrosz-Gómez

(2013) Proccedings of II Workshop on Adsorption, Catalysis and Porous Materials, Bogota-Colombia, pp 132–133.

33.

Yusof

Y.A.M.

and Malek

N.A.N.N.

(2009) J. Hazard. Mater. 162, 1019.

34.

Zarei

Niaei

Salari

and Khataee

(2010) J. Hazard. Mater. 173, 544.

35.

Zhong

L.-S.

J.-S.

Cao

A.-M.

Liu

Song

W.-G.

and Wan

L.-J.

(2007) Chem. Mater. 19, 1648.

Adsorptive Removal of Cr(VI) from Aqueous Solution on Hydrous Cerium—Zirconium Oxide. Part I: Process Optimization by Response Surface Methodology

Abstract

References